Can you over sparge

[lackofstyl]

So first of all I finaly got my membership paid. This is the best homebrew forum, and I am glad to be part of it. Second a question about sparging. I partial mash and use about 4 lbs. of grain and 1.25 quarts of water per lb. for the mash. When I sparge i top up the cooler with the recomended amount by beersmith, which is usually around half of the original volume. After adding the first and second run off to my kettle I top up with water for a full boil of 6.5 gallons. Should I sparge the top up water for the brewpot through the grains, or am I on the right track already.

 

[wwest]

Why not try it and check the gravity of the runnings? My understanding is that if it's really low (<1.010) then you risk extracting (undesirable) husk tannins. If not, you're just increasing your effciency.

 

[Beerrific]

Why not try it and check the gravity of the runnings? My understanding is that if it's really low (<1.010) then you risk extracting (undesirable) husk tannins. If not, you're just increasing your effciency.

I think it actually has to do with the pH and temperature of the sparge. High temp and high pH extracts excess tannins (this happens as the SG of the runnings drops).

I would mash, sparge with what you were planning then that volume again, no more than that. You could enter the recipe in your software and see what you should sparge with if the 1st and 2nd runnings were the total amount of wort (say 2.5 gallons), use those volumes then just top up.

 

[Got Trub?]

With batch sparging tannin extraction is less of an issue. You should be fine. The problem with fly sparging is that as the you continuously sparge the buffering capacity of the grain declines. Once you get down to a low specific gravity the pH climbs sharply and tannins are released. Temperature, while frequently cited, is not the issue or no one would be doing decoction mashing...